dlls/crypt32/context.c

   1 /*
   2  * Copyright 2006 Juan Lang
   3  *
   4  * This library is free software; you can redistribute it and/or
   5  * modify it under the terms of the GNU Lesser General Public
   6  * License as published by the Free Software Foundation; either
   7  * version 2.1 of the License, or (at your option) any later version.
   8  *
   9  * This library is distributed in the hope that it will be useful,
  10  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  11  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  12  * Lesser General Public License for more details.
  13  *
  14  * You should have received a copy of the GNU Lesser General Public
  15  * License along with this library; if not, write to the Free Software
  16  * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301, USA
  17  */
  18 #include <assert.h>
  19 #include <stdarg.h>
  20 #include "windef.h"
  21 #include "winbase.h"
  22 #include "wincrypt.h"
  23 #include "wine/debug.h"
  24 #include "wine/list.h"
  25 #include "crypt32_private.h"
  26
  27 WINE_DEFAULT_DEBUG_CHANNEL(crypt);
  28
  29 typedef enum _ContextType {
  30     ContextTypeData,
  31     ContextTypeLink,
  32 } ContextType;
  33
  34 typedef struct _BASE_CONTEXT
  35 {
  36     LONG        ref;
  37     ContextType type;
  38 } BASE_CONTEXT, *PBASE_CONTEXT;
  39
  40 typedef struct _DATA_CONTEXT
  41 {
  42     LONG                   ref;
  43     ContextType            type; /* always ContextTypeData */
  44     PCONTEXT_PROPERTY_LIST properties;
  45 } DATA_CONTEXT, *PDATA_CONTEXT;
  46
  47 typedef struct _LINK_CONTEXT
  48 {
  49     LONG          ref;
  50     ContextType   type; /* always ContextTypeLink */
  51     PBASE_CONTEXT linked;
  52 } LINK_CONTEXT, *PLINK_CONTEXT;
  53
  54 #define CONTEXT_FROM_BASE_CONTEXT(p, s) ((LPBYTE)(p) - (s))
  55 #define BASE_CONTEXT_FROM_CONTEXT(p, s) (PBASE_CONTEXT)((LPBYTE)(p) + (s))
  56
  57 void *Context_CreateDataContext(size_t contextSize)
  58 {
  59     void *ret = CryptMemAlloc(contextSize + sizeof(DATA_CONTEXT));
  60
  61     if (ret)
  62     {
  63         PDATA_CONTEXT context = (PDATA_CONTEXT)((LPBYTE)ret + contextSize);
  64
  65         context->ref = 1;
  66         context->type = ContextTypeData;
  67         context->properties = ContextPropertyList_Create();
  68         if (!context->properties)
  69         {
  70             CryptMemFree(ret);
  71             ret = NULL;
  72         }
  73     }
  74     return ret;
  75 }
  76
  77 void *Context_CreateLinkContext(unsigned int contextSize, void *linked, unsigned int extra,
  78  BOOL addRef)
  79 {
  80     void *context = CryptMemAlloc(contextSize + sizeof(LINK_CONTEXT) + extra);
  81
  82     TRACE("(%d, %p, %d)\n", contextSize, linked, extra);
  83
  84     if (context)
  85     {
  86         PLINK_CONTEXT linkContext = (PLINK_CONTEXT)BASE_CONTEXT_FROM_CONTEXT(
  87          context, contextSize);
  88         PBASE_CONTEXT linkedBase = BASE_CONTEXT_FROM_CONTEXT(linked,
  89          contextSize);
  90
  91         memcpy(context, linked, contextSize);
  92         linkContext->ref = 1;
  93         linkContext->type = ContextTypeLink;
  94         linkContext->linked = linkedBase;
  95         if (addRef)
  96             InterlockedIncrement(&linkedBase->ref);
  97         TRACE("%p's ref count is %d\n", context, linkContext->ref);
  98     }
  99     return context;
 100 }
 101
 102 void Context_AddRef(void *context, size_t contextSize)
 103 {
 104     PBASE_CONTEXT baseContext = BASE_CONTEXT_FROM_CONTEXT(context, contextSize);
 105
 106     InterlockedIncrement(&baseContext->ref);
 107 }
 108
 109 void *Context_GetExtra(const void *context, size_t contextSize)
 110 {
 111     PBASE_CONTEXT baseContext = BASE_CONTEXT_FROM_CONTEXT(context, contextSize);
 112
 113     assert(baseContext->type == ContextTypeLink);
 114     return (LPBYTE)baseContext + sizeof(LINK_CONTEXT);
 115 }
 116
 117 void *Context_GetLinkedContext(void *context, size_t contextSize)
 118 {
 119     PBASE_CONTEXT baseContext = BASE_CONTEXT_FROM_CONTEXT(context, contextSize);
 120
 121     assert(baseContext->type == ContextTypeLink);
 122     return CONTEXT_FROM_BASE_CONTEXT(((PLINK_CONTEXT)baseContext)->linked,
 123      contextSize);
 124 }
 125
 126 PCONTEXT_PROPERTY_LIST Context_GetProperties(void *context, size_t contextSize)
 127 {
 128     PBASE_CONTEXT ptr = BASE_CONTEXT_FROM_CONTEXT(context, contextSize);
 129
 130     while (ptr && ptr->type == ContextTypeLink)
 131         ptr = ((PLINK_CONTEXT)ptr)->linked;
 132     return (ptr && ptr->type == ContextTypeData) ?
 133      ((PDATA_CONTEXT)ptr)->properties : NULL;
 134 }
 135
 136 void Context_Release(void *context, size_t contextSize,
 137  ContextFreeFunc dataContextFree)
 138 {
 139     PBASE_CONTEXT base = BASE_CONTEXT_FROM_CONTEXT(context, contextSize);
 140
 141     if (InterlockedDecrement(&base->ref) == 0)
 142     {
 143         TRACE("freeing %p\n", context);
 144         switch (base->type)
 145         {
 146         case ContextTypeData:
 147             ContextPropertyList_Free(((PDATA_CONTEXT)base)->properties);
 148             dataContextFree(context);
 149             break;
 150         case ContextTypeLink:
 151             /* The linked context is of the same type as this, so release
 152              * it as well, using the same offset and data free function.
 153              */
 154             Context_Release(CONTEXT_FROM_BASE_CONTEXT(
 155              ((PLINK_CONTEXT)base)->linked, contextSize), contextSize,
 156              dataContextFree);
 157             break;
 158         default:
 159             assert(0);
 160         }
 161         CryptMemFree(context);
 162     }
 163     else
 164         TRACE("%p's ref count is %d\n", context, base->ref);
 165 }
 166
 167 void Context_CopyProperties(const void *to, const void *from,
 168  size_t contextSize)
 169 {
 170     PCONTEXT_PROPERTY_LIST toProperties, fromProperties;
 171
 172     toProperties = Context_GetProperties((void *)to, contextSize);
 173     fromProperties = Context_GetProperties((void *)from, contextSize);
 174     ContextPropertyList_Copy(toProperties, fromProperties);
 175 }
 176
 177 struct ContextList
 178 {
 179     PCWINE_CONTEXT_INTERFACE contextInterface;
 180     size_t contextSize;
 181     CRITICAL_SECTION cs;
 182     struct list contexts;
 183 };
 184
 185 struct ContextList *ContextList_Create(
 186  PCWINE_CONTEXT_INTERFACE contextInterface, size_t contextSize)
 187 {
 188     struct ContextList *list = CryptMemAlloc(sizeof(struct ContextList));
 189
 190     if (list)
 191     {
 192         list->contextInterface = contextInterface;
 193         list->contextSize = contextSize;
 194         InitializeCriticalSection(&list->cs);
 195         list->cs.DebugInfo->Spare[0] = (DWORD_PTR)(__FILE__ ": ContextList.cs");
 196         list_init(&list->contexts);
 197     }
 198     return list;
 199 }
 200
 201 static inline struct list *ContextList_ContextToEntry(struct ContextList *list,
 202  const void *context)
 203 {
 204     struct list *ret;
 205
 206     if (context)
 207         ret = (struct list *)Context_GetExtra(context, list->contextSize);
 208     else
 209         ret = NULL;
 210     return ret;
 211 }
 212
 213 static inline void *ContextList_EntryToContext(struct ContextList *list,
 214  struct list *entry)
 215 {
 216     return (LPBYTE)entry - sizeof(LINK_CONTEXT) - list->contextSize;
 217 }
 218
 219 void *ContextList_Add(struct ContextList *list, void *toLink, void *toReplace)
 220 {
 221     void *context;
 222
 223     TRACE("(%p, %p, %p)\n", list, toLink, toReplace);
 224
 225     context = Context_CreateLinkContext(list->contextSize, toLink,
 226      sizeof(struct list), TRUE);
 227     if (context)
 228     {
 229         struct list *entry = ContextList_ContextToEntry(list, context);
 230
 231         TRACE("adding %p\n", context);
 232         EnterCriticalSection(&list->cs);
 233         if (toReplace)
 234         {
 235             struct list *existing = ContextList_ContextToEntry(list, toReplace);
 236
 237             entry->prev = existing->prev;
 238             entry->next = existing->next;
 239             entry->prev->next = entry;
 240             entry->next->prev = entry;
 241             existing->prev = existing->next = existing;
 242             list->contextInterface->free(toReplace);
 243         }
 244         else
 245             list_add_tail(&list->contexts, entry);
 246         LeaveCriticalSection(&list->cs);
 247     }
 248     return context;
 249 }
 250
 251 void *ContextList_Enum(struct ContextList *list, void *pPrev)
 252 {
 253     struct list *listNext;
 254     void *ret;
 255
 256     EnterCriticalSection(&list->cs);
 257     if (pPrev)
 258     {
 259         struct list *prevEntry = ContextList_ContextToEntry(list, pPrev);
 260
 261         listNext = list_next(&list->contexts, prevEntry);
 262         list->contextInterface->free(pPrev);
 263     }
 264     else
 265         listNext = list_next(&list->contexts, &list->contexts);
 266     LeaveCriticalSection(&list->cs);
 267
 268     if (listNext)
 269     {
 270         ret = ContextList_EntryToContext(list, listNext);
 271         list->contextInterface->duplicate(ret);
 272     }
 273     else
 274         ret = NULL;
 275     return ret;
 276 }
 277
 278 void ContextList_Delete(struct ContextList *list, void *context)
 279 {
 280     struct list *entry = ContextList_ContextToEntry(list, context);
 281
 282     EnterCriticalSection(&list->cs);
 283     list_remove(entry);
 284     LeaveCriticalSection(&list->cs);
 285     list->contextInterface->free(context);
 286 }
 287
 288 void ContextList_Empty(struct ContextList *list)
 289 {
 290     struct list *entry, *next;
 291
 292     EnterCriticalSection(&list->cs);
 293     LIST_FOR_EACH_SAFE(entry, next, &list->contexts)
 294     {
 295         const void *context = ContextList_EntryToContext(list, entry);
 296
 297         TRACE("removing %p\n", context);
 298         list_remove(entry);
 299         list->contextInterface->free(context);
 300     }
 301     LeaveCriticalSection(&list->cs);
 302 }
 303
 304 void ContextList_Free(struct ContextList *list)
 305 {
 306     ContextList_Empty(list);
 307     list->cs.DebugInfo->Spare[0] = 0;
 308     DeleteCriticalSection(&list->cs);
 309     CryptMemFree(list);
 310 }